A new procedure for the determination of chromium species in polluted environmental samples by flame atomic absorption spectrometry was developed in this work. A new material containing 1,5-diphenylcarbazone included in a polymeric matrix was prepared and employed as a solid-phase extraction material for selective separation of Cr(III) ions under dynamic conditions. Chromium(III) ions were reta...

Various pollutants (e.g. boron and hexavalent chromium) are introduced into the aquatic environment from a variety of industrial operations causing damages to environment and affecting human health. Boron in irrigation water is of particular interest because it can have beneficial or toxic effect on plants, depending on its concentration. Pollution of the environment with hexavalent chromium (C...

This paper deals with Cr(VI) ion removal from water, by micro-alloyed aluminium composite (MAlC), under flow conditions. In a water environment the MAlC acts as a strong reducing agent. Dissolving it in water is accompanied by the generation of Al(III) ions and reduction of water to H 2 , with OH ions. The final product is insoluble Al(OH) 3 . A series of Cr(VI) model solutions, with initial pH...

A novel, simple p-dimethyl amino benzyl ethylene diamine reagent has been synthesized under ordinary laboratory conditions and this reagent was successfully applied for the determination of Chromium (VI) in various environmental samples. This reagent yields a red colored complex with chromium metal solution in sodium acetate-acetic acid buffer of pH 7.0. Maximum absorption was obtained at 560 n...

Acrylonitrile (AN) and 1-vinyl imidazole (VI) based hydrogel was prepared in bulk (macro) dimensions via redox polymerization technique. Afterward, this quaternized (positively charged) exposed to the amidoximation reaction. The hydrogels (quart-p(AN-co-VI), amid-p(AN-co-VI) p(VI)) characterized using fourier transform infrared spectroscopy (FT-IR) thermal gravimetric analysis (TGA). Swelling e...

Ethylenediaminetetraacetic (EDTA), cyclohexane-1,2-diaminetetraacetic (CDTA) and diethylenetriaminepentaacetic (DTPA) acids were investigated and compared as complexing agents for the speciation of chromium(VI/III), vanadium(V/IV) and iron(III/II) ions by capillary electrophoresis. The chromium(III) was selectively chelated with DTPA in order to impart a negative charge and similar mobility to ...

the potential of heat inactivated saccharomyces cerevisiae in the bioremoval and reduction ofcr (vi) ions from wastewaters was evaluated in terms of metal uptake in time and at equilibrium, andbiosorption efficiency, by varying ph, biosorbent doses, contact time and temperature, in batch mode. during the sorption process, the heat inactivated biomass of the yeast saccharomyces cerevisiae is cap...

Chromium(VI) compounds are known to be potent toxic and carcinogenic agents. Because chromium(VI) is easily taken up by cells and is subsequently reduced to chromium(III), the formation of paramagnetic chromium such as chromium(V) and chromium(III) is believed to play a role in the adverse biological effects of chromium(VI) compounds. The present report, uses electron spin resonance (ESR) spect...

Chromium occurs in the environment primarily in two valence states, trivalent chromium (Cr III) and hexavalent chromium (Cr VI). Exposure may occur from natural or industrial sources of chromium. Chromium III is much less toxic than chromium (VI). The respiratory tract is also the major target organ for chromium (III) toxicity, similar to chromium (VI). Chromium (III) is an essential element in...

A new time-based flow injection on-line solid phase extraction method for chromium(VI) and lead determination using flame atomic absorption spectrometry was developed. The use of hydrophobic poly-chlorotrifluoroethylene (PCTFE)-beads as absorbent in on-line preconcentration system was evaluated. Effective formation of ammonium pyrrolidine dithiocarbamate complexes and subsequently retention in ...